LEASES - Components of Lease Expense and Payments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Lessee, Lease, Description [Line Items]
Operating lease cost	$ 5,975	$ 6,061	$ 17,719	$ 18,398
Short-term lease cost	655	714	1,958	1,869
Variable lease cost	1,266	1,010	3,311	2,456
Total operating lease cost	7,896	7,785	22,988	22,723
Finance lease cost:
Amortization of right-of-use asset	735	742	2,239	2,321
Variable costs	211	209	641	667
Interest costs	103	93	265	290
Total finance lease cost	1,049	$ 1,044	3,145	3,278
Payments for lease liabilities			14,600	16,000
Lease liabilities arising from ROU			15,800	6,100
Finance leases cost included in property, plant and equipment	31,600		31,600		$ 26,600
Accumulated amortization related to finance leases	15,700		15,700		13,500
Principal payments, finance lease liabilities			932	820
Investing cash flows for finance lease liabilities			3,500
Operating cash flows for finance lease liabilities			300	300
Finance lease, disposed				2,300
Loss on sale of finance lease				$ 1,000
Finance lease liability	5,978		5,978		$ 5,459
Finance lease liability, current	$ 1,800		1,800
Repositioning of Wholesale Roaming Operations
Finance lease cost:
Right of use assets terminated			5,600
Lease liability terminated			5,900
Gain on lease termination			$ 300